High neutrophil-to-lymphocyte ratio in patients with melanoma treated with PD-1 inhibitor

This study wanted to find out if a high neutrophil-to-lymphocyte ratio (NLR) was related to the survival of patients with melanoma treated with PD-1 inhibitor treatment. The study found that the higher the NLR, the lower the chances of survival in these patients. 

One type of melanoma treatment involves PD-1 inhibitor drugs such as nivolumab (Opdivo) or pembrolizumab (Keytruda). These are immunotherapy drugs that help the immune system to detect and attack cancer cells.

Neutrophils and lymphocytes are white blood cells that makeup part of the immune system. It has previously been noticed that the number of neutrophils in comparison to the number of lymphocytes is related to how well a treatment works in patients with melanoma. However, it is not well known if the ratio of neutrophils to lymphocytes (NLR) is associated with poor survival in patients with melanoma treated with PD-1 inhibitors.

This study had 224 patients. All of the patients had advanced melanoma. All of the patients were treated with a PD-1 inhibitor drug. Blood was taken from the patients before they started treatment, and during treatment. The NLR was calculated for the patients at each blood test.

Before they started treatment, 28% of patients had an NLR of greater than 5 (high). The patients with a high NLR were more likely to have cancer in multiple places (metastatic cancer). The patients with a high NLR were more likely to be functioning at a lower level.

The patients were followed for 39 months after treatment started. The patients with a high NLR survived for half as long as the patients with a low NLR (less than 5). The treatment failed faster in patients with a high NLR. 

The study concluded that a high NLR is associated with worse outcomes in patients with melanoma treated with PD-1 inhibitors. The authors suggest that the NLR can identify the patients in which PD-1 inhibitors would not be a suitable treatment.

This was a small study. Also, it was based on medical records. Information might have been missing. This might have affected the results.